Apparatus for detecting the presence of suspended matter in fluids



March 23, 1954 w UHL 2,672,785

A. APPARATUS FOR DETECTING THE PRESENCE OF SUSPENDED MATTER IN FLUIDSFiled NOV. 30, 1949 I INVENTOR. 6 1?? u R N. UHL

ATTORNEY Patented Mar. 23, 1954 OFFICE APPARATUS FOR DETECTING THE PRES-ENCE 0F SUSPENDED MATTER IN FLUIDS Arthur W. Uhl, Inw ood, N. Y.,assignor, to Specialties, Development Corporation,

., a corporation of New Jersey Belleville,

Application November 30, 1949, Serial No. 130,291

4 Claims.

This invention relates to improvements in apparatus for detecting thepresence of suspended matter in fluids.

More specifically, the invention is directed to the detection of thepresenc of smoke in the air of one or more protected spaces or areas,such as fur vaults, record vaults, air ducts, storage rooms, or otherspaces or general areas requiring protection against fire, through thedetection of smoke. It is to be understood, however, that this inventionmay be employed for other purposes, as for detection of the presence ofsuspended matter in other fluids, or for determination of the density offluids in containers or enclosures.

When the invention is utilized for the detection of smoke and the givingof an alarm when smoke is detected, smoke detecting apparatus of thephotoelectric cell type is employed. Such apparatus generally includes alight source or detector lamp and a rays of light on th photoelectriccell, whereby the cell will generate an electric current, the magnitudeof which is reduced by the presence of smoke in the path of the rays oflight, thereby actuating a relay to effect the closing of a circuit toan alarm.

In smoke detecting apparatus of the character indicated, theaccumulation of dust or dirt on the lens, or the detector lamp and/or onother interior parts of the apparatus, reduce the intensity of the raysof light falling on the photoelectric cell, whereby the current outputof the cell is reduced resulting in a fals fire alarm. In such apparatusalso it is often necessary to disassemble the entire apparatus in orderto clean of dust or dirt off the parts. is one or th objects of the toprovide a smoke detecting apparatus of the character indicated whereinthe possibility of accumulation of dust or dirt on any of the partswithin th apparatus is reduced to a minimum.

Another object of the invention resides in the provision of smokedetecting apparatus wherein the detector lamp is enclosed in a sealedcasing to prevent dust or dirt contacting the lamp and wherein the lampand lens are mounted for ready removal from th apparatus.

Another object of the invention is the provision of apparatus of thecharacter indicated, wherein readily removable screen or filter means isprovided in the path of air entering the apparatus, whereby to screen orfilter the air before entering the detector tube proper.

A further object of the invention is the propresent invention lenssystem for directing vision of a-readily removable section of the de--tector tube, whereby to provide ready access to the removable screenorfilter means, the detector lamp and lens system. i

Other and further objects of the present invention will b obviousscribed in greater detail in connection with the accompanying drawings,inwhich:

Figure l is a longitudinal sectional view of the smoke detectingvention;

Figure 2 is a cross-sectional view taken online 22 of Figure 1; and lFigure 3 is a, plan view of one end of the apparatus.

Referring to the drawings in detail, the smoke detecting apparatus shownin Figure 1 comprises a housing [0, which is made in two sections l2 andI4 detachably secured to each other by screws It. The section #2 has anair or smoke inlet l8 leading from a protected space or area (notshown), and has a filter conical mesh tube, the smaller end of which isdisposed adjacent the inlet l8, and its larger end having a bushing orcollar and adapted to be received end of the section it of the A smokeor detector tector lamp 34 removably mounted in one end ofa cylindricalcasing 36 and a lens 38 mounted in the other end thereof. The casing 36has an opening 3'! in the cylindrical wall thereof, whereby, when thedetector tube, the lamp can easily be removed through said opening forreplacement. The cas-j lens 38 seals the other end thereof, wherebyasthe invention is deapparatus of the present intube 2!] mounted. therein.The filtertube is in the form of a frusto-- 22 secured thereto casing isremoved from the smoke and air is prevented from entering the casing.

A photoelectric cell 40 is mounted in a casing 42 at the end of thesmoke or detector tube 26 opposite the light source and in the directpath of rays of light from the detector lamp 34.

The detector tube 26 has a plurality of inlet openings 46 in the wallthereof adjacent the inner end of the casing 36, and an outlet opening48 is provided adjacent the other end of the detector tube. The outlet48 communicates with an exhaust conduit 50 in which a motor drivenblower 52 or other suction device is mounted for v drawing air or smokefrom the protected space or area through the inlet t8 in the housing in,through the filter tube 20, past the spacer mem bers 28, through theopenings 46, into the detec tor tube 26 and hence into the path of thelight rays from the detector lamp 34, and out of the opening 48 throughthe exhaust conduit to the atmosphere. The air drawn into the detectortube 26, in passing between the spacer members 28, tends to retain thedetector lamp and its casing cool. i

The electric conductors for the detector lamp and the photoelectric cellare enclosed in a conduit 54, the opposite ends of which are connectedto and supported by junction boxes 56 and 58' which are mountedrespectively on the housing l and the detector tube 26.

Any conventional relay for operating an alarm circuit may be connectedinto the photoelectric cell circuit and employed with the apparatus ofthe present invention, hence it is not necessary to illustrate anddescribe such relay and alarm circuit.

When it is desired to remove the light source or detector lamp forreplacement, or to remove the lens or filter means for cleaning, it ismerely necessary to loosen the screws I6, withdraw the section I! fromthe section M, then remove the casing 36, replace the light bulb throughthe opening 31, clean the lens, and again insert the casing in place.When the section [2 has been removed it is a simple operation to merelywith-- draw the filter tube or screen 26 from the section l2, wherebythe same may be cleaned.

While the casing 36 is frictionally held in the; end of the smoke tube26, means may be provided to retain the casing in place in the event thefrictional engagement between the casing and the inner wall of the tube26 is insufiicient to retain the casing in place under all conditions ofuse of the apparatus. The means provided for the said purpose comprisesa U-shaped spring member 66, one endof which is secured to the collar 22of the filter tube by a screw 62, and the other end of which is inengagement with a projection 64' on the base of the socket for detectorlamp 34. As will be seen removal of the filter tube, in the manner previously described, the spring member 60 will be removed therewithpermitting the removal of the casing.

Insofar as the novel features of the present invention are concerned,the apparatus may be employedas a visual detector for suspended matterin fluids, by having the detector'tube 26 made of transparent material,such as glass, plastic on the like, or by providing a transparent windowinlthe tube-26,. whereby when no suspended matter is present in the airin the tube, or being drawn therethrough, the light rays will not bevisible but when suspended matter is present the from Figure 1, upon 4same will be illuminated by the rays of light and be readily visible.

From the foregoing it will be seen that the present invention provides anovel smoke detect-X ing apparatus, wherein the light source iscompletely sealed in a casing to prevent dust or dirt contacting thelight bulb, and wherein the parts are-readily removable for cleaning orreplacement.

While I have illustrated and described a preferred embodiment of myinvention, it is to be understood that I do not wish to be limited tothat precise structure, as obviously various changes and modificationsmay be made therein without departing from the spirit and scope of myinvention.

I claim:

1. Apparatus for detecting the presence of suspended matter in fluidscomprising an elongate cylindrical tube having a fluid inlet opening inits side wall adjacently spaced from one end and having a fluid outletopening adjacent its other end, a sealed casing removably positioned insaid tube between said inlet opening and the adjacent end of the tubeincluding a light source, a lens forming a closure between said lightsource and said inlet opening and a closure for said last mentioned andof said tube, a housing section surrounding said tube in coaxiallyspaced relation thereto to provide a passage and extending inwardly fromsaid last mentioned end of said tube to beyond said inlet opening,closure means between said tube and the inner end of said housingsectioma second housing section extending outwardiy from said lastmentioned end of said tube and having a central opening at its outerend, means for removably securing the outer end of said first housingsection and the inner end of said second housing section, a generallytubular screen positioned in said second housing section having its walladjacent the interioroi said sec- 0116 housing section at it inner endand'having its wall-converging towards the outer endof said secondhousing section and adjacent spaced from said opening therein, and anelement on the converging end or" said screen facing said second housingsection opening.

2. Apparatus for detecting the presence of suspended matter in fluidscomprising an elongate tubular member having a fluid inlet opening inits side wall adja'oently' spaced from one end and having a. fluidoutlet opening adjacent its other end, a housing section surroundingsaid member in coaxially spaced relation thereto and extend ing inwardlyfrom saidfirst mentionedend of the member tobeyond said inlet opening,said section having a fluid entrance at its, outer end, an electriclamp, and a tubular casing for said lamp having imperiorate end wallsand having a side wall formed with an opening in sealing engagement withthe inner wall of saidinember to close said opening to prevent fluidfrom contacting the latter, said casing being removably positioned insaid member between said inlet opening and the adjacent end of themember, the space between said housing section and the member providinga fluid flow passage from the fluid entrance to the fluid inlet openingin said mem ber by -passing said sealed easing.

3. Apparatus for detecting the presence of suspended matter in fluidscomprising an elongate tubular member having a fluid inlet opening in.

its side wall adjacently spaced from one end and having a fluid outletopening adjacent its other end, ahousing section surrounding said memherin coaxially spaced relation thereto and extending inwardly from saidfirst mentioned end of the member to beyond said inlet opening, atubular extension removably secured to the outer end of said section andhaving a fluid entrance at its outer end, a light source, and a casingfor said light source to prevent fluid from contacting the latter havingan opening in the wall thereof and having imperforate end walls, saidcasing being removably positioned in said member between said inletopening and the adjacent end of the member and rendered accessible uponthe removal of said extension, the wall of said member cooperating withthe casing to effectively close said opening when the casing is sopositioned, and the space between said housing secticn and the memberproviding a fluid flow passage from the fluid entrance to the fluidinlet opening in said member by-passing said sealed casing.

4. Apparatus for detecting the presence of suspended matter in fluidscomprising an elongate tubular member having a fluid inlet opening inits side wall adjacently spaced from one end and having a fluid outletopening adjacent its other end, a housing section surrounding saidmember in coaxially spaced relation thereto and extending inwardly fromsaid first mentioned end of the member to beyond said inlet opening,said section having a fluid entrance at its outer end.

a light source, a casing for said light source removably positioned insaid member between said inlet opening and the adjacent end of themember, said casing having an opening in the wall thereof to provideacces to the light source when the casing is removed from the member,the wall of the member cooperating with the casing to effectively closesaid opening when the casing is in place, whereby to prevent fluid fromcontacting said light source, the space between said housing section andthe member providing a fluid flow passage from the fluid entrance to thefluid inlet opening in said member by-passing said sealed casing.

ARTHUR W. UHL.

References Cited in the file of this patent UNITED STATES PATENTS NumberName Date 1,969,626 Simon et a1 Aug. '7, 1934 2,042,095 Grant, Jr May26, 1936 2,301,367 Cahusac et a1 Nov. 10, 1942 2,306,588 Cahusac et a1.Dec. 29, 1942 2,468,740 Else May 3, 1949 FOREIGN PATENTS Number CountryDate 668,449 Germany Dec. 3, 1938

